The present invention relates to the printer arts. It finds particular application in conjunction with a modular carriage assembly for a high-speed, high-performance ink jet printer and will be described with particular reference thereto. However, it should be appreciated that the present invention may also find application in conjunction with other types of printing devices and applications where a print carriage traverses across a media.
FIG. 1 illustrates an exemplary printing device 1, such as an ink jet printer. The device 1 includes a frame 2 housing a media transport assembly 4. The media transport assembly feeds a media 6, such as individual sheets or continuous rolls of paper through a printing flat zone, designated generally as 8, in a first direction along a media feed axis X. A carriage assembly 10 is driven by drive means such as a motor (not shown) transversely across the printing flat zone on one or more guide rails 12 in both directions along a carriage scan axis Y.
A controller 14 controls the operation of the media transport assembly 4 and the carriage assembly 10 to cause ink to be printed or otherwise deposited on the media 6 from one or more arrays of print nozzles or jets that are associated with the carriage assembly 10, as the media is advanced in a direction along the media feed axis X.
FIG. 2 shows one configuration for the carriage assembly 10 that incorporates multiple print nozzle arrays 16a-16f. Each of the nozzle arrays 16a-16f are spaced-apart in a side-by side configuration along the carriage scan axis Y. Further, coincident pairs of the nozzle arrays 16a and 16d, 16b and 16e, and 16c and 16f are staggered or offset relative to each other along the media feed axis X. This side-by-side configuration provides a small "printing flat zone", defined as the distance 18 between the leading edges of nozzle arrays 16a and 16d and the trailing edges of nozzle arrays 16c and 16f in a media feed or x-direction. However, this side-by-side configuration disadvantageously provides for a large distance 20 between the leftmost nozzle array 16a and the rightmost nozzle array 16f, resulting in a greater overscan inefficiency of the printer.
Overscan efficiency is a measure of carriage stroke or excursion relative to media (i.e. paper) width. The greater the distance that the carriage must travel during each excursion across the media, the greater the size or form factor that the printing device must be in order to accommodate a carriage with such an excursion. Further, the configuration of FIG. 2 results in a larger carriage assembly form factor in order to accommodate the side-by-side nozzle array configuration.
FIG. 3 shows another configuration for the carriage assembly 10 that incorporates multiple print nozzle arrays 16. In particular, the nozzle arrays 16 are oriented in a stacked configuration along the media scan X-axis. That is, each of the nozzle arrays 16a-16f are staggered or offset relative to each other along the media feed axis X. Further, coincident pairs of the nozzle arrays 16a and 16d, 16b and 16e, and 16c and 16f are spaced-apart along the carriage scan axis Y. This stacked configuration advantageously provides a smaller distance 20 between the leftmost nozzle arrays 16a and 16d and the rightmost nozzle arrays 16c and 16f when compared to the side-by-side configuration of FIG. 2.
The reduced distance 20 advantageously provides for reduced overscan inefficiency. However, the stacked configuration disadvantageously provides an increased printing flat zone 18, when compared to the side-by-side configuration of FIG. 2. The greater the width of the printing flat zone, the greater the size that the printing device must be in order to accommodate the printing flat zone. Further, the carriage assembly configuration of FIG. 3 results in a larger carriage form factor in order to accommodate the stacked nozzle assembly configuration.
Accordingly, it has been considered desirable to develop a new and improved carriage assembly for a high-speed, high-performance, printing device that meets the above-stated needs and overcomes the foregoing difficulties and others while providing better and more advantageous results.